displayio operations that read from an SD card (e.g., OnDiskBitmap) will interfere with other SD card operations and can cause lockup. To work around this problem, do not read or write files on the SD while the display is updating, and vice versa.

Does this mean that nothing can be changed on the screen when SD card access is taking place? Is there a small risk with automatic refreshes with code that does

Slap an image on screen

Open another file and read it

could still cause a problem because the actual writes to the screen may occur between statements in 2? Is that low risk or should there be a forced screen refresh after 1 to ensure all changes are flushed to it or a disable of automatic refreshes?